1. Field of the Invention
The present invention relates to an image forming apparatus including a storage unit that once stores a sheet having an image formed thereon in the apparatus.
2. Description of the Related Art
Conventionally, an image forming apparatus such as a copying machine or a printer includes a storage unit that once stores sheets each having an image formed thereon in the apparatus so that a user can receive only the his/her own sheets such that others do not see the sheets.
Japanese Patent Application Laid-Open No. 7-125909 discusses an image forming apparatus including a plurality of storage units that once stores sheets each having an image formed thereon in the apparatus in addition to a normal discharge tray provided on an upper surface of an apparatus body and commonly used by a plurality of users. The sheets stored in the storage units cannot be seen from outside the apparatus. In the image forming apparatus, the storage units are respectively assigned to users, and sheets are distributed into the different storage units for each of the users. When receiving the sheets, the user instructs the image forming apparatus to discharge the sheets so that the sheets stored in the storage unit corresponding to the user who has issued the discharge instruction are discharged out of the apparatus. Thus, the user can receive only the his/her own sheets each having the image formed thereon such that others do not see the sheets.
In Japanese Patent Application Laid-Open No. 7-125909, one storage unit is assigned to one user. Thus, if a larger number of users than the number of storage units instruct an image forming apparatus to perform printing, sheets cannot be distributed into the different storage units for each of the users. If four users instruct an image forming apparatus including three storage units to perform printing, for example, sheets of the remaining one user cannot be stored in the storage units. More specifically, only sheets of one user can be stored in one storage unit.